To quote the blurb:
We are alone in the universe. After 1,000 years of searching humankind simply believes that there is nothing out there. Space is a magificent, but sterile, wilderness. That's the received wisdom, anyway. But a new expedition investigating a mysteriously aborted mission 27 years earlier is about to turn that wisdom on its head.
I don't normally quote other reviewers in my reviews but given the enthusiasm and identity of this one, I'm making an exception:
Jack McDevitt is that splendid rarity, a story-teller first and a science fiction writer second. In his ability to absolutely rivet the reader it seems to me that he is the logical heir to Isaac Asimov and Arthur C Clarke. If you've never read McDevitt before you couldn't find a better book to start with than Slow Lightning - a nail-biting neo-Gothic tale that blends mystery, horror, and a fascinating look at how first contact with an utterly alien species might happen.
I have in fact read and reviewed half-a-dozen of McDevitt's other books here, namely the Priscilla Hutchins series (Slow Lightning is a stand-alone, published in 2000). While the author certainly has an inventive imagination, I am not quite as enthusiastic as King, since I find his writing style not entirely to my liking. If you are curious I suggest you look at my earlier McDevitt reviews.
A couple of detailed points: I was intrigued by the author's suggestion that the reaction of humanity to the apparent lack of any other civilisation would be to lose interest in further exploration, with colonies gradually shutting down and being abandoned. It seems reasonable - if there is nothing there to see, why bother to go looking?
The other point concerns the book's title, as explained in the text:
The nearby nebula NGC2024, stretching for light years across the restless sky, was a kaleidoscope of bright and dark lanes, of exquisite geometry, of glowing surfaces and internal fires. Enormous lightning bolts moved through it, but it was so far that they seemed frozen in space.
"Slow lightning," said Solly, "Like the mission."
Kim looked at the nebula. "How do you mean?"
"We've known for a long time that contact might eventually happen, maybe would have to happen, and that when it did it would change everything. Our technology, our sense of who we are, our notions of what the universe is. We've seen this particular lightning strike coming and we've played with the idea of what it might mean for at least twelve hundred years. We've imagined that other intelligences exist, we've imagined them as fearsome and gentle, as impossibly strange and remarkably familiar, as godlike, as incapable, as indifferent. Well, I wonder whether the bolt is about to arrive. With you and me at the impact point."